This invention relates to electronic systems and more particularly relates to a system and method for quantifying vehicular damage information.
Vehicular accidents are a common occurrence in many parts of the world and, unfortunately, vehicular accidents, even at low impact and separation velocities, are often accompanied by injury to vehicle occupants. It is often desirable to reconcile actual occupant injury reports to a potential for energy based on vehicular accident information. Trained engineers and accident reconstruction experts evaluate subject vehicles involved in a collision, and based on their training and experience, may be able to arrive at an estimated change in velocity (xe2x80x9cxcex94Vxe2x80x9d) for each the subject vehicles. The potential for injury can be derived from knowledge of the respective xcex94V""s for the subject vehicles.
However, involving trained engineers and accident reconstruction experts in all collisions, especially in the numerous low velocity collisions, is often not cost effective.
In one embodiment of the present invention, a computer program product, encoded in computer readable media, includes program instructions, which, when executed by a processor, are operable to receive input information regarding damaged vehicle components for at least one vehicle, categorize damage zones with respect to the location of the bumper of a vehicle, categorize a vehicle component with respect to its location on the vehicle, and estimate the change in the vehicle""s velocity as a result of a collision based on the damaged vehicle components information. The information regarding damaged vehicle components includes particular damaged vehicle components, locations of damaged vehicle components, depth information corresponding to the damaged vehicle components, and an overall vehicle damage rating.
In a further embodiment, a computer system executing the computer program product is operable to compare the overall vehicle damage rating to a crash test vehicle damage rating, and to estimate whether to use crash test data to determine the change in the vehicle""s velocity, based on the comparison and the location of damaged components. The executing computer program product further compares characteristics of a damaged vehicle to characteristics of vehicles for which crash test data is available, and determines whether crash test data for a particular vehicle is applicable to the damaged vehicle. The executing computer program product then determines a coefficient of restitution to use in estimating the change in the vehicle""s velocity.
In a further embodiment, the executing computer program product is operable to estimate the change in the vehicle""s velocity based either on the crash data, or the on conservation of momentum. The change in vehicle velocity is later input to a multi-method change in velocity combination generator.
In a further embodiment, the computer program product includes a change in velocity determination module which computationally estimates the change in ok vehicle velocity based on estimates of deformation energy and principal forces. Deformation energy may be estimated using a one-way spring model. Principal forces may be estimated based on at least one stiffness parameter and the damage depth information. In a further embodiment, the executing computer program product is operable to compare principal forces for at least two vehicles and determine whether the stiffness parameters, the depth information, and/or the principal forces may be adjusted within predetermined thresholds to substantially balance the principal forces.
In a further embodiment, the executing computer program product is operable to estimate closing velocity based on an estimate of a coefficient of restitution. A distribution of changes in velocity may be determined by varying parameters used to estimate the change in velocity. Statistical error functions in the distribution of changes in velocity may also be estimated and used to vary the parameters. In a further embodiment, distribution of changes in velocity are estimated using stochastic simulation.
In a further embodiment, the computer program product includes override/underride logic that is operable to determine stiffness parameters based on the position of the vehicle""s bumper relative to the position of another vehicle""s bumper.
In a further embodiment, the computer program product includes a multi-method change in velocity generator that is operable to estimate the change in the vehicle""s velocity as a result of a collision based on a plurality of estimation methods including estimation based on one set of crash test data, estimation based on another set of crash test data, and estimation based on conservation of momentum. In a further embodiment, the results of each estimation method are weighted and combined to determine a final estimate for the change in the vehicle""s velocity. In a further embodiment, the results for each estimation method may be weighted using a statistical method, such at the t-test.
In another embodiment, a computer-implemented method for estimating the change in velocity of a vehicle as a result of a collision, is provided which includes
acquiring information regarding damaged components of at least one vehicle,
assigning a damage rating to the at least one vehicle,
determining whether to utilize crash test data for a first estimate of the change in velocity for the at least one vehicle based at least partially on the damage rating,
determining a second estimate of the change in velocity for the at least one vehicle based on conservation of momentum,
determining a third estimate of the change in velocity for the at least one vehicle based on deformation energy, and
determining a final estimate of the change in velocity for the at least one vehicle based on at least one of the first, second, and third estimates of the change in velocity.
In a further embodiment, the method includes determining whether to utilize crash test data for a first estimate of the change in velocity for the at least one vehicle based on the location of damaged components.
In a further embodiment, the method includes comparing the location of damaged components on vehicles involved in the same collision to determine whether to use crash test data to estimate the change in at least one of the vehicles"" velocity.
In a further embodiment, the method includes comparing characteristics of a damaged vehicle to characteristics of vehicles for which crash test data is available, and determining whether crash test data for a particular vehicle is applicable to the damaged vehicle.
In a further embodiment, the method includes estimating principal forces based on at least one stiffness parameter and the depth information.
In a further embodiment, the method includes comparing principal forces for at least two vehicles and determining whether vehicle parameters may be adjusted within predetermined thresholds to substantially balance the principal forces.
In a further embodiment, the method includes determining a distribution of changes in velocity by varying parameters used to estimate the change in velocity and estimating statistical error in the distribution of changes in velocity.
In a further embodiment, the method includes varying parameters according to a stochastic simulation.
In a further embodiment, the method includes determining stiffness parameters based on the position of the vehicle""s bumper relative to the position of another vehicle""s bumper.
In a further embodiment, the method includes weighting the first, second, and third estimates of the change in velocity and combining the weighted estimates to determine the final estimate for the change in the vehicle""s velocity.
In a further embodiment, the method includes using a statistical method for weighting the results of each estimation method.